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	/*
	* Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package java.net;

	import java.io.ObjectStreamException;

	/**
	* This class represents an Internet Protocol version 4 (IPv4) address.
	* Defined by <a href="http://www.ietf.org/rfc/rfc790.txt">
	* <i>RFC 790: Assigned Numbers</i></a>,
	* <a href="http://www.ietf.org/rfc/rfc1918.txt">
	* <i>RFC 1918: Address Allocation for Private Internets</i></a>,
	* and <a href="http://www.ietf.org/rfc/rfc2365.txt"><i>RFC 2365:
	* Administratively Scoped IP Multicast</i></a>
	*
	* <h3> <A NAME="format">Textual representation of IP addresses</a> </h3>
	*
	* Textual representation of IPv4 address used as input to methods
	* takes one of the following forms:
	*
	* <blockquote><table cellpadding=0 cellspacing=0 summary="layout">
	* <tr><td>{@code d.d.d.d}</td></tr>
	* <tr><td>{@code d.d.d}</td></tr>
	* <tr><td>{@code d.d}</td></tr>
	* <tr><td>{@code d}</td></tr>
	* </table></blockquote>
	*
	* <p> When four parts are specified, each is interpreted as a byte of
	* data and assigned, from left to right, to the four bytes of an IPv4
	* address.

	* <p> When a three part address is specified, the last part is
	* interpreted as a 16-bit quantity and placed in the right most two
	* bytes of the network address. This makes the three part address
	* format convenient for specifying Class B net- work addresses as
	* 128.net.host.
	*
	* <p> When a two part address is supplied, the last part is
	* interpreted as a 24-bit quantity and placed in the right most three
	* bytes of the network address. This makes the two part address
	* format convenient for specifying Class A network addresses as
	* net.host.
	*
	* <p> When only one part is given, the value is stored directly in
	* the network address without any byte rearrangement.
	*
	* <p> For methods that return a textual representation as output
	* value, the first form, i.e. a dotted-quad string, is used.
	*
	* <h4> The Scope of a Multicast Address </h4>
	*
	* Historically the IPv4 TTL field in the IP header has doubled as a
	* multicast scope field: a TTL of 0 means node-local, 1 means
	* link-local, up through 32 means site-local, up through 64 means
	* region-local, up through 128 means continent-local, and up through
	* 255 are global. However, the administrative scoping is preferred.
	* Please refer to <a href="http://www.ietf.org/rfc/rfc2365.txt">
	* <i>RFC 2365: Administratively Scoped IP Multicast</i></a>
	* @since 1.4
	*/

	public final
	class Inet4Address extends InetAddress {
	final static int INADDRSZ = 4;

	/** use serialVersionUID from InetAddress, but Inet4Address instance
	* is always replaced by an InetAddress instance before being
	* serialized */
	private static final long serialVersionUID = 3286316764910316507L;

	/*
	* Perform initializations.
	*/
	static {
	init();
	}

	Inet4Address() {
	super();
	holder().hostName = null;
	holder().address = 0;
	holder().family = IPv4;
	}

	Inet4Address(String hostName, byte addr[]) {
	holder().hostName = hostName;
	holder().family = IPv4;
	if (addr != null) {
	if (addr.length == INADDRSZ) {
	int address = addr[3] & 0xFF;
	address \|= ((addr[2] << 8) & 0xFF00);
	address \|= ((addr[1] << 16) & 0xFF0000);
	address \|= ((addr[0] << 24) & 0xFF000000);
	holder().address = address;
	}
	}
	holder().originalHostName = hostName;
	}
	Inet4Address(String hostName, int address) {
	holder().hostName = hostName;
	holder().family = IPv4;
	holder().address = address;
	holder().originalHostName = hostName;
	}

	/**
	* Replaces the object to be serialized with an InetAddress object.
	*
	* @return the alternate object to be serialized.
	*
	* @throws ObjectStreamException if a new object replacing this
	* object could not be created
	*/
	private Object writeReplace() throws ObjectStreamException {
	// will replace the to be serialized 'this' object
	InetAddress inet = new InetAddress();
	inet.holder().hostName = holder().getHostName();
	inet.holder().address = holder().getAddress();

	/**
	* Prior to 1.4 an InetAddress was created with a family
	* based on the platform AF_INET value (usually 2).
	* For compatibility reasons we must therefore write the
	* the InetAddress with this family.
	*/
	inet.holder().family = 2;

	return inet;
	}

	/**
	* Utility routine to check if the InetAddress is an
	* IP multicast address. IP multicast address is a Class D
	* address i.e first four bits of the address are 1110.
	* @return a {@code boolean} indicating if the InetAddress is
	* an IP multicast address
	* @since JDK1.1
	*/
	public boolean isMulticastAddress() {
	return ((holder().getAddress() & 0xf0000000) == 0xe0000000);
	}

	/**
	* Utility routine to check if the InetAddress in a wildcard address.
	* @return a {@code boolean} indicating if the Inetaddress is
	* a wildcard address.
	* @since 1.4
	*/
	public boolean isAnyLocalAddress() {
	return holder().getAddress() == 0;
	}

	/**
	* Utility routine to check if the InetAddress is a loopback address.
	*
	* @return a {@code boolean} indicating if the InetAddress is
	* a loopback address; or false otherwise.
	* @since 1.4
	*/
	public boolean isLoopbackAddress() {
	/* 127.x.x.x */
	byte[] byteAddr = getAddress();
	return byteAddr[0] == 127;
	}

	/**
	* Utility routine to check if the InetAddress is an link local address.
	*
	* @return a {@code boolean} indicating if the InetAddress is
	* a link local address; or false if address is not a link local unicast address.
	* @since 1.4
	*/
	public boolean isLinkLocalAddress() {
	// link-local unicast in IPv4 (169.254.0.0/16)
	// defined in "Documenting Special Use IPv4 Address Blocks
	// that have been Registered with IANA" by Bill Manning
	// draft-manning-dsua-06.txt
	int address = holder().getAddress();
	return (((address >>> 24) & 0xFF) == 169)
	&& (((address >>> 16) & 0xFF) == 254);
	}

	/**
	* Utility routine to check if the InetAddress is a site local address.
	*
	* @return a {@code boolean} indicating if the InetAddress is
	* a site local address; or false if address is not a site local unicast address.
	* @since 1.4
	*/
	public boolean isSiteLocalAddress() {
	// refer to RFC 1918
	// 10/8 prefix
	// 172.16/12 prefix
	// 192.168/16 prefix
	int address = holder().getAddress();
	return (((address >>> 24) & 0xFF) == 10)
	\|\| ((((address >>> 24) & 0xFF) == 172)
	&& (((address >>> 16) & 0xF0) == 16))
	\|\| ((((address >>> 24) & 0xFF) == 192)
	&& (((address >>> 16) & 0xFF) == 168));
	}

	/**
	* Utility routine to check if the multicast address has global scope.
	*
	* @return a {@code boolean} indicating if the address has
	* is a multicast address of global scope, false if it is not
	* of global scope or it is not a multicast address
	* @since 1.4
	*/
	public boolean isMCGlobal() {
	// 224.0.1.0 to 238.255.255.255
	byte[] byteAddr = getAddress();
	return ((byteAddr[0] & 0xff) >= 224 && (byteAddr[0] & 0xff) <= 238 ) &&
	!((byteAddr[0] & 0xff) == 224 && byteAddr[1] == 0 &&
	byteAddr[2] == 0);
	}

	/**
	* Utility routine to check if the multicast address has node scope.
	*
	* @return a {@code boolean} indicating if the address has
	* is a multicast address of node-local scope, false if it is not
	* of node-local scope or it is not a multicast address
	* @since 1.4
	*/
	public boolean isMCNodeLocal() {
	// unless ttl == 0
	return false;
	}

	/**
	* Utility routine to check if the multicast address has link scope.
	*
	* @return a {@code boolean} indicating if the address has
	* is a multicast address of link-local scope, false if it is not
	* of link-local scope or it is not a multicast address
	* @since 1.4
	*/
	public boolean isMCLinkLocal() {
	// 224.0.0/24 prefix and ttl == 1
	int address = holder().getAddress();
	return (((address >>> 24) & 0xFF) == 224)
	&& (((address >>> 16) & 0xFF) == 0)
	&& (((address >>> 8) & 0xFF) == 0);
	}

	/**
	* Utility routine to check if the multicast address has site scope.
	*
	* @return a {@code boolean} indicating if the address has
	* is a multicast address of site-local scope, false if it is not
	* of site-local scope or it is not a multicast address
	* @since 1.4
	*/
	public boolean isMCSiteLocal() {
	// 239.255/16 prefix or ttl < 32
	int address = holder().getAddress();
	return (((address >>> 24) & 0xFF) == 239)
	&& (((address >>> 16) & 0xFF) == 255);
	}

	/**
	* Utility routine to check if the multicast address has organization scope.
	*
	* @return a {@code boolean} indicating if the address has
	* is a multicast address of organization-local scope,
	* false if it is not of organization-local scope
	* or it is not a multicast address
	* @since 1.4
	*/
	public boolean isMCOrgLocal() {
	// 239.192 - 239.195
	int address = holder().getAddress();
	return (((address >>> 24) & 0xFF) == 239)
	&& (((address >>> 16) & 0xFF) >= 192)
	&& (((address >>> 16) & 0xFF) <= 195);
	}

	/**
	* Returns the raw IP address of this {@code InetAddress}
	* object. The result is in network byte order: the highest order
	* byte of the address is in {@code getAddress()[0]}.
	*
	* @return the raw IP address of this object.
	*/
	public byte[] getAddress() {
	int address = holder().getAddress();
	byte[] addr = new byte[INADDRSZ];

	addr[0] = (byte) ((address >>> 24) & 0xFF);
	addr[1] = (byte) ((address >>> 16) & 0xFF);
	addr[2] = (byte) ((address >>> 8) & 0xFF);
	addr[3] = (byte) (address & 0xFF);
	return addr;
	}

	/**
	* Returns the IP address string in textual presentation form.
	*
	* @return the raw IP address in a string format.
	* @since JDK1.0.2
	*/
	public String getHostAddress() {
	return numericToTextFormat(getAddress());
	}

	/**
	* Returns a hashcode for this IP address.
	*
	* @return a hash code value for this IP address.
	*/
	public int hashCode() {
	return holder().getAddress();
	}

	/**
	* Compares this object against the specified object.
	* The result is {@code true} if and only if the argument is
	* not {@code null} and it represents the same IP address as
	* this object.
	* <p>
	* Two instances of {@code InetAddress} represent the same IP
	* address if the length of the byte arrays returned by
	* {@code getAddress} is the same for both, and each of the
	* array components is the same for the byte arrays.
	*
	* @param obj the object to compare against.
	* @return {@code true} if the objects are the same;
	* {@code false} otherwise.
	* @see java.net.InetAddress#getAddress()
	*/
	public boolean equals(Object obj) {
	return (obj != null) && (obj instanceof Inet4Address) &&
	(((InetAddress)obj).holder().getAddress() == holder().getAddress());
	}

	// Utilities
	/*
	* Converts IPv4 binary address into a string suitable for presentation.
	*
	* @param src a byte array representing an IPv4 numeric address
	* @return a String representing the IPv4 address in
	* textual representation format
	* @since 1.4
	*/

	static String numericToTextFormat(byte[] src)
	{
	return (src[0] & 0xff) + "." + (src[1] & 0xff) + "." + (src[2] & 0xff) + "." + (src[3] & 0xff);
	}

	/**
	* Perform class load-time initializations.
	*/
	private static native void init();
	}

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